Apparatus having a functional structure delimited by a frame structure and method for producing same

ABSTRACT

An apparatus includes a semiconductor-based substrate with a functional structure that is formed in or on the semiconductor-based substrate. The apparatus includes a frame structure surrounding the functional structure and includes a coating that covers the functional structure and is delimited by the frame structure.

This application claims the benefit of German Application No.102018209024.6, filed on Jun. 7, 2018, which application is herebyincorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to an apparatus having a coating of afunctional structure delimited by a frame structure and to a method forproducing same. The present disclosure furthermore relates to aframe-type structure for uniformly arranging thin films made ofnanomaterials.

BACKGROUND

Semiconductor-based apparatuses, such as sensors and/or actuators, canhave a multi-layer construction. Some of the layers of the layerconstruction can be semiconductor-based layers, for example in the formof wafers and/or epitaxially grown layers. Other layers can be appliedby a suitable process for the arrangement, for example by way of gasphase deposition, printing processes or mechanical placement orpositioning methods.

Apparatuses in which arranged layers having a high degree of precisionand a high degree of uniformity are obtained would be desirable.

SUMMARY

Exemplary embodiments provide an apparatus having a semiconductor-basedsubstrate with a functional structure that is formed in or on thesemiconductor-based substrate. The apparatus comprises a frame structuresurrounding the functional structure. The apparatus furthermorecomprises a coating that covers the functional structure and isdelimited by the frame structure.

A further exemplary embodiment provides a method for producing astructure. The method comprises providing a semiconductor-basedsubstrate having a functional structure that is arranged in or on thesemiconductor-based substrate. The method comprises arranging a framestructure such that the frame structure surrounds the functionalstructure. The method comprises arranging a coating such that thecoating covers the functional structure and is delimited by the framestructure.

Further exemplary embodiments are defined in the dependent patentclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments will be explained below with reference to theappended drawings. In the figures:

FIG. 1 shows a schematic side sectional view of an apparatus accordingto an exemplary embodiment;

FIG. 2 shows a schematic side sectional view of an apparatus accordingto an exemplary embodiment, in which a coating includes a first layerand a second layer;

FIG. 3 shows a schematic side sectional view of an apparatus accordingto an exemplary embodiment, in which a functional structure regionallyprotrudes with respect to the semiconductor-based substrate;

FIG. 4 shows a schematic side sectional view of an apparatus accordingto an exemplary embodiment, in which a frame structure at leastpartially fills one or more recesses in the semiconductor-basedsubstrate;

FIG. 5 shows a schematic side sectional view of an apparatus accordingto an exemplary embodiment, in which the frame structure is at leastpartially formed by the recesses;

FIG. 6 shows a schematic plan view of the apparatus in FIG. 1.

FIG. 7 shows a schematic plan view of the apparatus in FIG. 1 accordingto an exemplary embodiment, in which the frame structure has an opening;

FIG. 8 shows a schematic plan view of an apparatus according to anexemplary embodiment, in which the functional structure comprisesinterdigital electrodes;

FIG. 9a shows a schematic plan view of a known apparatus comprising astructure of interdigital electrodes;

FIG. 9b shows a schematic plan view of an apparatus according to anexemplary embodiment having the same structure as in FIG. 9a , butadditionally having the frame structure;

FIG. 10 shows a schematic flowchart of a method according to anexemplary embodiment; and

FIG. 11 shows a schematic flowchart of a method that can be performedfor example to at least partially provide a coating in the methodaccording to FIG. 10.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Before exemplary embodiments are explained in more detail below withreference to the drawings, it should be noted that identical,functionally equivalent or identically acting elements, objects and/orstructures are denoted in the various figures with the same referencesigns, which means that the description of said elements illustrated inthe various exemplary embodiments is interchangeable or can be appliedto one another.

The following exemplary embodiments relate to an apparatus having afunctional structure. The functional structure can be an element whichis deflectable by way of an actuator and/or sensor, such as a membranestructure, a post structure, a beam structure or the like. Alternativelyor additionally, the functional structure can also be immovable and beembodied for example such that, based on an interaction with physical,chemical or other variables to be sensed, it changes a property that isthen determinable. Examples of such structures are for example fluidsensors, in particular chemosensors, which can change an electricproperty, such as a resistance value, based on an interaction oradsorption of a material from the fluid in a sensor environment. Oneexample of a chemosensor within the meaning of the present disclosure isa gas sensor. In accordance with an exemplary embodiment, the functionalstructure comprises an electrode structure having one or more electrodesand/or conductor tracks. In other words, any desired portion of astructure formed during a technology process is understood to be afunctional structure.

The following exemplary embodiments furthermore relate to a coatingcovering the functional structure. Functional structures in accordancewith exemplary embodiments described here can be arranged both forfunctionalization and, alternatively or additionally, as mechanicalprotection. Functionalization can be attained for example by way of anelectrical conductivity of the coating, which provides an electricallyconductive function of the coating. Alternatively or additionally, touchprotection, dust protection or the like can be provided by virtue of thecoating covering the functional structure. In accordance with exemplaryembodiments, it is alternatively or additionally possible to provideprotection against chemical influences, for example by facilitating orpreventing interaction with a medium by way of the functional structure.

FIG. 1 shows a schematic side sectional view of an apparatus 10according to an exemplary embodiment. The apparatus 10 comprises asemiconductor-based substrate, for example comprising a siliconmaterial, gallium arsenide material, and/or another semiconductormaterial. The semiconductor-based substrate 12 can be present forexample in the form of a wafer, for example before singulation intoindividual sensors, actuators or chips, but can also be present inalready singulated form. The semiconductor-based substrate 12 cancomprise a plurality of layers in different and/or combined sub-layersof the semiconductor-based substrate 12, for example silicon orpolysilicon layers, which can be covered entirely or partially byinsulating materials, such as silicon oxide. Alternatively oradditionally, other or further materials can be arranged, such assilicon nitride materials.

The apparatus 10 comprises a functional structure 14 that is introducedfor example in and/or on the semiconductor-based substrate 12 and formsa common surface with the semiconductor-based substrate 12. Thefunctional structure 14 can be any desired sensor device and/or actuatordevice. Alternatively or additionally, the functional structure 14 canalso be a circuit arrangement comprising any desired number of conductortracks and/or circuit components. The functional structure can compriseone or more electrodes, wherein said electrodes can be arranged on orunder the substrate surface, for example as buried electrodes or aselectrodes which are arranged under the substrate surface but are freelyaccessible.

The apparatus 10 comprises a frame structure 16 surrounding thefunctional structure 14. The frame structure 16 can be arranged on thesurface 18 of the semiconductor substrate 12; for example, the surface18 is the surface that forms the common surface with the functionalstructure 14. Alternatively, the frame structure 16 can also be arrangedin any other plane. The frame structure 16 can be arranged such that, atleast in the case of a projection of the functional structure 14 and ofthe frame structure 16 into the surface 18 of the semiconductor-basedsubstrate 12, that is to say into a common plane, the functionalstructure 14 is arranged within the frame structure 16. This can beachieved by virtue of the frame structure 16 continuously and/orcompletely enclosing the functional structure 14. Alternatively, theframe structure 16 can also have openings such that the frame structuresurrounds the functional structure 14 merely incompletely. Although theframe structure 16 is described such that the functional structure 14 isenclosed, this does not rule out that one or more electrical contactlocations or supply lines of the functional structure 14 are located ina region of the frame structure 16, for example under the framestructure, over the frame structure, or form a layer of the framestructure.

The apparatus 10 comprises a coating 22 that covers the functionalstructure 14 and is delimited by the frame structure 16. The coating 22can here cover the functional structure 14 partially or completely. Thecoating 22 can completely cover a region 24 that is completely orincompletely enclosed by the frame structure 16. On account of the useof the frame structure 16, the arrangement of the coating 22 can be suchthat the coating 22 can be arranged with a high degree of precision withrespect to a lateral position of the coating 22 along directions xand/or y parallel to the surface 18. Alternatively or additionally, thecoating 22 can also be attained with a high degree of precision withrespect to a layer thickness, but for example not necessarily parallelto the z-direction, which can also be understood to be the thicknessdirection. Alternatively or additionally, it is possible to obtain ahigh degree of uniformity of the coating 22, specifically on thefunctional structure 14. For example, the frame structure 16 may besuitable for printing and/or dispensing processes, in which a liquid,such as an ink material or the like, is applied over the functionalstructure 14. The definition of the region 24 by way of the framestructure 16 makes possible the arrangement of the liquid within theregion 24 and uniform drying in the region 24. For example what areknown as coffee rings, which can be obtained through non-uniform drying,on the functional structure 14 can thus be avoided.

FIG. 2 shows a schematic side sectional view of an apparatus 10 a, inwhich the coating 22 has a first layer 22-1 and a second layer 22-2,wherein alternatively or additionally merely one layer or more than twolayers can be arranged, for example three or more, five or more, ten ormore, or a greater number. Each of the layers can be arrangedindependently of other layers over the entire region of the framestructure 16 or merely in partial regions, as long as the framestructure 16 is formed in this way. For example, when combining a first,possibly electronically insulating, layer with a second, possiblyelectrically conductive, layer, the second layer may be arranged merelyin partial regions of the frame structure 16, and the first layer may bearranged contiguously, for example. This makes it possible for differentportions to be formed to be electrically insulating and electricallyconductive into the frame structure 16, with different materials beingable to be used herein, for example a silicon material, such aspolysilicon, silicon oxide and/or silicon nitride.

The layers 22-1 and 22-2 can have the same or different materials. Forexample, the layers 22-1 and/or 22-2 can comprise a nanomaterial, forexample a carbon nanomaterial. One example of a carbon nanomaterial isgraphene. Alternatively or additionally, it is possible for one or moreother 2D nanomaterials, polymer materials, metal and/or metal oxidenanoparticles, and any desired material combinations or compositematerials from the previously mentioned materials to be arranged. Forexample, a multilayer coating can be obtained by way of multi-stepprinting.

An identical or comparable height of the frame structure 16 and of thecoating 22 can be obtained for example by performing an etching process,a polishing process, or a grinding process. The apparatus 10 in FIG. 1can represent for example a state before such a grinding process.Alternatively, it is also possible to arrange an amount of coatingmaterials such that a corresponding height is obtained after receivingthe coating 22, for example by drying.

FIG. 3 shows a schematic side sectional view of an apparatus 10 b, inwhich the functional structure 14 is arranged on the semiconductor-basedsubstrate 12, for example on the surface 18. For example, these can beregions or layers which are grown on, arranged or not removed and makeit possible that the functional structure 14 regionally protrudes withrespect to the semiconductor-based substrate 12. The coating 22 cannevertheless cover the functional structure 14. A distance between thefunctional structure 14 and the frame structure 16 makes possible thecovering of the functional structure 14 with the coating 22 even on sidesurfaces of the functional structure 14.

As shown in FIG. 1 and FIG. 2, the functional structure 14 arranged onthe semiconductor-based substrate 12 according to FIG. 3 can also makepossible partial or even complete encapsulation of the functionalstructure 14 by the semiconductor-based substrate 12 and the coating 22.

As shown in FIG. 1, FIG. 2 and FIG. 3, the frame structure can bearranged on the substrate side, for example the substrate surface 18,and protrude with respect to the substrate surface. It should be pointedout that the substrate side can certainly be understood to be thesurface 18, but it can also be another substrate surface, and/or theframe structure can also cover other parts of the apparatus, for examplecircuit parts or the like. A dimension or height h of the framestructure 16 parallel to the thickness direction z, which extends forexample parallel to a surface normal of the surface 18, can be at least10 nm and at most 1000 μm, at least 50 nm and at most 800 μm, or atleast 100 nm and at most 1 μm.

FIG. 4 shows a schematic side sectional view of an apparatus 10 caccording to an exemplary embodiment, in which the frame structure 16 atleast partially fills one or more recesses 26 in the semiconductor-basedsubstrate 12, such that a material of the frame structure 16 mayapproach the surface 18 or is at least applied very thinly, that is tosay has a layer thickness of less than 10 nm, for example. This makes itpossible that, when depositing a material of the coating 22, a repellingforce between the material of the coating 22 and the material of theframe structure 16 prevents an overflow of material of the coating 22over the frame structure 16, for example due to surface forces that mayarise when using liquids. In particular in printing methods fordepositing an ink or dispersion comprising the coating material of thecoating and a solvent, the applied ink can be delimited by such surfaceforces in terms of its spatial extent/distribution, that is to say thespread thereof can be confined. Such a surface effect can beadvantageously utilized in other exemplary embodiments, too, for examplein the apparatus 10, 10 a and/or 10 b with respect to the materials ofthe frame structure and of the coating 22.

A maximally attainable layer thickness of the ink and consequently ofthe coating 22 can be influenced based on an amplitude or strength ofsuch surface forces. The amplitude of the surface forces can beinfluenced for example by a suitable material selection and/or by way ofdimensions of the frame structure, for example a frame width, which inFIG. 4 can be understood to be a dimension of the frame structure 16along the x-direction. For example, the functional structure 14 can alsopartially project beyond the surface 18 of the semiconductor-basedsubstrate 12 and still be completely covered by the coating 22. Such adelimiting property of the frame structure 16 can also be utilized inaccordance with the other frame structures described here, but in thiscase a height or depth of the frame structure may already offersufficient delimitation security.

The coating 22, or the material applied for arranging the coating 22,and a material of the frame structure 16 can exhibit for exampleopposite or repelling properties, for example can be formed incomplementary fashion with respect to a hydrophobic property and ahydrophilic property. In accordance with an exemplary embodiment, thecoating 22 comprises a hydrophilic coating material. The frame structure16 can comprise a hydrophobic material. The frame structure 16 cancomprise a structurable material. This includes for example a polymermaterial, such as polyimide. Alternatively or additionally, thestructurable material can comprise other materials, for example aphotoresist, such as SU-8, polymethyl methacrylate (PMMA), silicon oxide(SiO₂), silicon nitride (SiN) and/or a combination thereof. The framestructure can be embodied for example by performing at least one stepduring or at the end of a photo lithographic method for producing theapparatus 10, 10 a, 10 b and/or 10 c.

Alternatively, a complementary embodiment can also be effected by way ofthe coating 22 comprising a hydrophobic coating material and the framestructure 16 comprising a hydrophilic material.

Hydrophobic coating material can be easily soluble or suspendable in ahydrophobic solvent. In the same way, hydrophilic coating material canbe easily soluble or suspendable in a hydrophilic solvent. There arealso possibilities for dissolving or suspending a hydrophobic materialof the coating 22 such that a hydrophilic material mix that is easilycombinable with a hydrophobic material of the frame structure 16 yetbrings about identical material properties of the coating 22 and of theframe structure 16 in the dried state of the coating 22 is obtained.

Unlike in FIG. 1, FIG. 2 and FIG. 3, the frame structure 16 has, forexample, a dimension h of 0, wherein the frame structure 16 canalternatively also protrude with respect to the surface 18.

FIG. 5 shows a schematic side sectional view of an apparatus 10 d inaccordance with an exemplary embodiment, in which the frame structure 16is at least partially formed by the depressions 26, which means that theframe structure 16 forms a trench in the substrate side, for example ina substrate surface 18. This allows the medium used for arranging thecoating 22 to flow off or over into the depressions 26, which means thatthe coating 22 can also be partially located in the depressions 26.

The depression 26 can also partially be filled with a material forforming the frame structure 16, which can also correspond to a merelypartial recess 26 in FIG. 4 that is filled with the material of theframe structure 16. A depth of the depressions 26 can likewise beunderstood to be the dimension h and have the same dimensions. Startingfrom the surface 18, it is possible for merely the direction along thez-direction to be swapped around if the frame structure according toFIG. 4 or 5 is compared to the frame structures according to FIG. 1,FIG. 2 and/or FIG. 3.

FIG. 6 shows a schematic plan view of the apparatus 10, wherein thestatements are also valid for other ones of the apparatuses describedhere, for example the apparatus 10 a, 10 b, 10 c and/or 10 d. The framestructure 16 encloses the region 24 as a surrounding structure, forexample as a depression, as a filled depression, and/or as a protrusionwith respect to a corresponding surface of the semiconductor-basedsubstrate 12. The coating 22 can be homogeneous in the region 24, whichmeans it can have a low surface waviness and/or identical, continuousmaterials. The arrangement of the frame structure 16 makes possible thearrangement of the material of the coating 22 in the region 24 andspreading of the material in the region 24. A subsequent hardening,strengthening and/or drying process can permit homogeneous drying of thematerial of the coating 22, with the result that the coating 22 isobtained with a hardly disturbing or non-disturbing artefact or evenwith the avoidance of disturbing artefacts such as coffee rings. It isthus possible, for example, for an artefact, for example a coffee ringartefact, to form despite the frame structure 16. By way of positioningthe frame structure 16 such that the frame structure 16 encloses thefunctional structure 14 and there is possibly a distance between thefunctional structure 14 and the frame structure 16 in the case of aprojection into the common plane, the formation of the artefact can becontrolled or moved into a region of the frame structure and/or of saiddistance. Here, the artefact does not disturb or negligibly disturbs thefunction of the apparatus because the coating is obtained uniformly inthe region of the functional structure 14. In other words: Shoulddisturbing artefacts such as coffee rings nevertheless arise, they canbe located either on and/or at the inner periphery of the framestructure 16, but not on the functional structure, which is uniformlycovered with a coating 22.

Based on different tasks of the frame structure 16 during the receivingof the coating 22, a frame width 28 can be at least 10 nm and at most 10mm, at least 50 nm and at most 5 mm, or at least 100 nm and at most 1mm. The frame width can be understood to be the shortest connectionbetween an outer side 321 and an inner side 322 of the frame structure16, wherein the inner side 322 can be understood to be the side of theframe structure 16 that faces the coating 22, and the outer side 321 canbe understood to be the side of the frame structure 16 that faces awayfrom the coating 22. A varying dimension 28 can result in differentproperties with respect to thermal capacitance, hydrophilicity and/orhydrophobicity, such that the properties obtained are settable based onthe frame width 28.

FIG. 7 shows a schematic plan view of the apparatus 10 according to anexemplary embodiment, in which the frame structure 16 has an opening 34connecting the outer side 321 to the inner side 322. Alternatively, theapparatus 10 can also have more than one opening 34 in the framestructure 16, or, as is illustrated for example in FIG. 6, no opening.The opening 34 makes possible an arrangement of other elements in thecut-out region and/or any desired utilization of said region. Theopening 34 can be formed here such that it is small enough to stillprevent the material of the coating 22 from flowing through it duringthe manufacturing process. Providing a plurality of openings 34 thusmakes possible for example the arrangement or production of the framestructure 16 with little material outlay and/or with low material stressacting on the semiconductor substrate 12 during cooling.

In addition to delimiting the coating 22, the frame structure 16 canalso be formed to be electrically conductive, in particular with respectto the apparatuses 10, 10 a, 10 b and/or 10 c. This makes possiblefurther functionalization of the frame structure 16, for example by atleast partially substituting further or other conductor trackstherewith.

A frame structure 16 that is formed from provided or arranged material,as described for example in connection with FIG. 1, FIG. 2, FIG. 3and/or FIG. 4, can comprise one material layer, but can also be embodiedin multilayer form, which likewise makes possible a greater degree offunctionalization. Different layers can have different properties thatare able to be adapted to one another with respect to electricalconductivity, thermal conductivity, hydrophobicity and/orhydrophilicity.

FIG. 8 shows a schematic plan view of an apparatus 80 according to anexemplary embodiment, in which the functional structure 14 comprisesinterdigital electrodes that are surrounded or enclosed by the framestructure 16 and are able to be contacted via outer, possibly uncoated,electrodes 481 and 482.

FIG. 9a shows a plan view of a known apparatus comprising a structure ofinterdigital electrodes which are able to be contacted by the electrodes481 and 482. It serves as a negative example without a frame structure.The coating 22 is formed non-uniformly with the formation of what areknown as coffee rings. In addition, the figure shows uncontrolledflowing out of the coating 22 in a region 49.

FIG. 9b shows a plan view of an apparatus 90 according to an exemplaryembodiment having the same structure as in FIG. 9a , but additionallyhaving the frame structure 16 that encloses the functional structure 14.A homogeneous coating 22 can be achieved in this way.

In other words, FIGS. 9a and 9b demonstrate an implementation inaccordance with exemplary embodiments. FIG. 9a shows printing of acarbon nanomaterial ink on a resistive sensor. By using the framestructure, as is illustrated in FIG. 9b , a material aggregation atdrying peripheries (coffee ring effect) on the functional structure 14can be avoided and thus uniform film formation can be accomplished. InFIG. 9b , the frame structure is formed as a polyimide frame and effectsan effective coating formation by virtue of the carbon nanomaterial inkbeing delimited.

Exemplary embodiments thus create transistors or chemosensors, whereinthe exemplary embodiments are not limited hereto. Knowledge gainedrelates to the fact that a frame is formed around the region of interestso as to be able to uniformly deposit nanomaterial thin films here,which results in a high reproducibility of the production process.Exemplary embodiments permit the production of apparatuses formonitoring air quality. Alternative chemosensors with othernanomaterials and composite materials can also be formed. The exemplaryembodiments described here furthermore permit printing of thin films,which makes it possible to obtain thin-film apparatuses, such asnanomaterial transistors, nano-material detectors and the like.

Exemplary embodiments make it possible to obtain uniform layers ofnanomaterials, in particular by using printing methods, for exampleinkjet printing methods. Problems such as mismatches between viscosityof the solvent and/or the coffee ring formation, that is to say amaterial aggregation at the peripheries of the pattern that impair thequality of the apparatuses, in particular by impairing the uniformity ofthe thin film arranged, can be overcome with the exemplary embodimentsdescribed herein.

As opposed to solutions that propose a low viscosity of the solvents,which permits immediate evaporation after application, the resultingdisadvantages are overcome, according to which:

1. the provision of the inks based on such solvents is challenging andobtaining a stable dispersant with nanomaterials is difficult.

2. while low-viscosity liquids work well in laboratories, they exhibitlow throughput in printing technology. These technologies are hardlyscalable. Many of the known production inkjet printers are suitable forthe use of viscosities of greater than 8 cP.

3. another approach is the modification of the surface energy of thesubstrate to stop spreading of the ink and minimize the coffee ringeffect, but such pre-treatments mean that the properties of thesubstrate layer are changed and difficult to monitor, control and/orkeep constant over a specific time period.

Exemplary embodiments offer the possibility of easily and reproduciblyarranging layers, in particular nanomaterial layers.

Exemplary embodiments relate to the arrangement of a frame-typestructure that delimits the spreading of the ink into the previouslydefined region. The frame structure offers the advantages that:

1. high-viscosity liquids and/or inks having high surface tension can beused;

2. after filling the frame with the ink and slow drying thereof, uniformcoverage of the area of the region 24 with the nanomaterial thin-film isobtained. The region 24 has interdigital electrodes, for example;

3. the coffee ring (material aggregation at the periphery of thepattern), which could be produced by drying and can result ininhomogeneous material distribution, can be moved outside the electrodearea, for example by virtue of the coffee ring being obtained at theperipheral structure 16 which is arranged outside the electrode regionsor the functional structure;

4. the ink or liquid can be delimited such that it does not flow intoadjacent regions where it may be undesirable; and

5. due to the frame structure, multiple printing methods of differentnanomaterials over the same region are made possible because it makespossible more degrees of freedom in the ink parameters, such asviscosity and surface tension.

FIG. 10 shows a schematic flowchart of a method 1000 according to anexemplary embodiment. The method 1000 comprises a step 1010 forproviding a semiconductor-based substrate having a functional structurethat is arranged in or on the semiconductor-based substrate, for examplethe functional structure 14 that is arranged on or in thesemiconductor-based substrate 12. The method 1000 comprises a step 1020for arranging a frame structure, such as the frame structure 16, suchthat the frame structure surrounds the functional structure. The methodfurthermore comprises a step 1030 for arranging a coating such that thecoating covers the functional structure and is delimited by the framestructure. The coating can be the coating 22, for example. It should bepointed out at this point that the functional structure can be arrangedbefore, after or during the production or provision of the framestructure. For example, the frame structure can be produced around thefunctional structure 14, for example by using a photolithographicprocess. Alternatively, the region 24 can also be defined before thefunctional structure 14 is arranged and the functional structure isarranged in the region 24. Alternatively or additionally, it is likewisepossible to use a same process step to at least partially produce thefunctional structure 14 and to at least partially produce the framestructure 16.

FIG. 11 shows a schematic flowchart of a method 1100 that can beperformed for example to at least partially provide or arrange thecoating in step 1030.

In a step 1110, a liquid comprising the coating material is provided.This can be for example nanomaterials dispersed in a solvent.

In a step 1120, the liquid is arranged in an inner region of the framestructure such that the liquid completely covers the inner region. Theliquid can be arranged, for example, in the region 24. By usinghigh-viscosity liquids, the frame structure can also have openings.

Step 1130 comprises drying the inner region such that the coatingmaterial is left behind as the coating. Optionally, preferably afterdrying 1130 and with another performance of steps 1120 and 1130, it ispossible to arrange a further layer with the liquid, which can makepossible for example a reduction or decrease in faults or airinclusions.

Likewise optionally, and as an alternative to the repetition of thesteps 1120 and 1130, it is possible for the method 1100 to be repeatedby performing the steps 1110, 1120 and 1130 again, for example by virtueof another liquid being provided in step 1110, which means that anotherlayer in the coating can be obtained, as is described for example inconnection with apparatus 10 a. This can also be understood to mean thatthe method 1000 can be performed such that a second liquid is arrangedin the inner region after the inner region is dried, wherein the secondliquid has a second coating material. The inner region can be driedagain, such that the second coating material forms a layer on thecoating.

The exemplary embodiments described herein, in particular the method1000 and/or 1100, can be performed such that the substrate comprises asemiconductor wafer, wherein the method is repeatedly performed on thewafer level, which means a plurality of frame structures are filledduring a printing step.

Although some aspects were described in connection with an apparatus, itis to be understood that these aspects also represent a description ofthe corresponding method, which means that a block or a structuralelement of an apparatus should also be understood to be a correspondingmethod step or a feature of a method step. Analogously, aspectsdescribed in connection with a, or as a, method step, also represent adescription of a corresponding block or detail or feature of acorresponding apparatus.

The above-described exemplary embodiments merely represent anillustration of the principles of the present invention. It is to beunderstood that modifications and variations of the arrangements anddetails described herein will be apparent to other persons skilled inthe art. It is therefore intended that the invention be limited only bythe scope of protection of the following patent claims and not by thespecific details that were presented here with reference to thedescription and the explanation of the exemplary embodiments.

What is claimed is:
 1. An apparatus, comprising: a semiconductor-based substrate having a functional structure formed in or on the semiconductor-based substrate; a frame structure surrounding the functional structure, wherein the frame structure comprises a first vertical sidewall and a second vertical sidewall; and a coating that covers the functional structure and is delimited by the frame structure, wherein the coating comprises a carbon nanomaterial ink, wherein the coating comprises at least one first planar layer having a planar top surface and a planar bottom surface and one second planar layer having a planar bottom surface, and wherein the at least one first planar layer and one second player layer are laterally delimited by the first vertical sidewall and the second vertical sidewall.
 2. The apparatus as claimed in claim 1, wherein the coating completely covers an inner region of the frame structure.
 3. The apparatus as claimed in claim 1, wherein the coating comprises a homogeneous coating.
 4. The apparatus as claimed in claim 1, wherein the frame structure is arranged on a substrate side, and wherein the frame structure protrudes with respect to a substrate surface.
 5. The apparatus as claimed in claim 4, wherein the frame structure has a height of at least 10 nm and at most 1,000 μm.
 6. The apparatus as claimed in claim 1, wherein the frame structure is arranged on a substrate side, and wherein the frame structure forms a trench in the substrate side.
 7. The apparatus as claimed in claim 6, wherein the frame structure has a depth of at least 10 nm and at most 1,000 μm.
 8. The apparatus as claimed in claim 1, wherein the coating comprises a hydrophilic coating material and wherein the frame structure comprises a hydrophobic material.
 9. The apparatus as claimed in claim 1, wherein the coating comprises a hydrophobic coating material and in which the frame structure comprises a hydrophilic material.
 10. The apparatus as claimed in claim 1, wherein the frame structure comprises a frame width between an inner side of the frame structure and an outer side of the frame structure having a dimension of at least 10 nm and at most 10 mm.
 11. The apparatus as claimed in claim 1, wherein the frame structure comprises an electrically conductive frame structure.
 12. The apparatus as claimed in claim 1, wherein the frame structure comprises at least one first layer and one second layer.
 13. The apparatus as claimed in claim 1, wherein the functional structure comprises an electrode structure.
 14. The apparatus as claimed in claim 1, wherein the frame structure comprises a structurable material.
 15. The apparatus as claimed in claim 1, wherein the functional structure is configured to provide an electrically conductive function and/or a protective function against mechanical and/or chemical influences.
 16. The apparatus as claimed in claim 1, comprising a chemosensor or a transistor.
 17. An apparatus, comprising: a semiconductor-based substrate having a functional structure formed in or on the semiconductor-based substrate; a frame structure surrounding the functional structure, wherein the frame structure comprises a first vertical sidewall and a second vertical sidewall; and a coating that covers the functional structure, the coating comprising a first planar layer having a planar top surface and a planar bottom surface and a second planar layer having a planar top surface and a planar bottom surface, wherein the first planar layer and the second planar layer are both laterally delimited by the first vertical sidewall and the second vertical sidewall of the frame structure.
 18. An apparatus, comprising: a semiconductor-based substrate having a functional structure formed on the semiconductor-based substrate; a frame structure surrounding the functional structure, wherein the frame structure comprises a first vertical sidewall and a second vertical sidewall; and a coating having first and second planar layers that covers the functional structure and is laterally delimited by the first vertical sidewall and the second vertical sidewall of the frame structure, wherein the frame structure comprises polysilicon, silicon oxide and/or silicon nitride, and wherein the first and second planar layers each comprise a planar top surface and a planar bottom surface. 